linuxrwlocks/testcase2.c

   1 #include <stdio.h>
   2 #include <threads.h>
   3 #include <stdatomic.h>
   4 #include "wildcard.h"
   5
   6 #include "librace.h"
   7 #include "linuxrwlocks-wildcard.h"
   8
   9 rwlock_t mylock;
  10 int shareddata;
  11
  12 atomic_int x, y;
  13
  14 static void a(void *obj)
  15 {
  16         if (!write_can_lock(&mylock))
  17                 return;
  18
  19         if (write_trylock(&mylock)) {
  20                 atomic_store_explicit(&x, 17, relaxed);
  21                 write_unlock(&mylock);
  22         }
  23 }
  24
  25 static void b(void *obj)
  26 {
  27         if (write_trylock(&mylock)) {
  28                 atomic_store_explicit(&x, 16, relaxed);
  29                 write_unlock(&mylock);
  30         }
  31
  32         if (!read_can_lock(&mylock))
  33                 return;
  34         if (read_trylock(&mylock)) {
  35                 atomic_load_explicit(&x, relaxed);
  36                 read_unlock(&mylock);
  37         }
  38 }
  39
  40 int user_main(int argc, char **argv)
  41 {
  42         thrd_t t1, t2;
  43         atomic_init(&mylock.lock, RW_LOCK_BIAS);
  44         atomic_init(&x, 0);
  45         atomic_init(&y, 0);
  46
  47         thrd_create(&t1, (thrd_start_t)&a, NULL);
  48         thrd_create(&t2, (thrd_start_t)&b, NULL);
  49
  50         thrd_join(t1);
  51         thrd_join(t2);
  52
  53         return 0;
  54 }